Kanye West has been hailed a "rock star" by JAY-Z after he triumphed in the U.K and U.S album charts this week. West's new album Graduation beat rap rival 50 Cent's Curtis to the top of the charts after they were released on the same day (11Sep07). And Jay-Z is proud his pal's hard work is being rewarded. He tells Entertainment Weekly, "It makes me proud as someone who's watched his growth from the beginning, when he came in as a hungry producer, to now he's a rock star. "I'm happy for him on that level. And I'm excited for creativity as well, because I think that's a win for that as well. You know, people mimic success. And in order to mimic that success, you have to put in a lot of work. You have to really care about the music." Jay-Z also predicted 50 Cent - who threatened to retire if he lost out to West in the battle of the albums - will "bounce back". He adds, "I think when you face any type of adversity it makes you dig deep ... everyone goes through it, all the greats go through it. In his music, he hadn't gone through any type of adversity. He'll come back and make great music."